Balloon angioplasty is a widely accepted method of opening blockages in the coronary arteries. The balloon catheter was introduced experimentally in the early 1960's and was first applied clinically in the late 1970's. It has since assumed a major therapeutic role in the treatment of single and multiple vessel coronary artery disease (Baumgartner, H. R., 1963, Z. Ges. Exp. Med., 137:227). However in some patients after successful treatment by balloon angioplasty, arterial restenosis occurs. This time however the narrowing of the inner diameter (ID) of the artery is caused by growth (proliferation) of endothelial cells in the areas of irritation caused by the balloon angioplasty. Thus reblockage occurs not by cholesterol build-up but by build up of endothelial cells on the inner wall of the artery reducing the inner diameter (ID) of the artery leading to an infarct. In man, the restenotic lesion consists almost entirely, though not exclusively of vascular smooth muscle cells (Glazier, J. J., Williams, M. G., Madden, S. and Rickards, A. F., 1990, J. Roy. Coll. Phys. Lond., 24:292). Their accumulation within the artery lumen is a result of cell migration and proliferation. (It is believed that the Medial Smooth muscle cells migrate through defects in the damaged internal elastic laminar, and peripheral blood leucocytes, attach initially to the exposed subendothelial matrix, enter the injured arterial wall, and are converted into lipid-laden foam-cells in the presence of elevated levels of cholesterol-rich lipoprotein (Ferns G. A. A.; Forster, L. A.; Stewart-Lee, A; Konneh M.; Nourooz-Zadeh, J., Anggard E E; (1992) PROBUCOL inhibits neo-internal thickening and macrophage accumulation after balloon injury in the cholesterol-fed rabbit. PROC. Natl. ACAD, Sci., USA 89: 11312-11316). The two events (cell migration and proliferation) are almost certainly due to the coordinated interaction of a number of different cytokines likely released by early accumulation of macrophages at the site of original tissue injury. This narrowing of the inner diameter (ID) of tubular walls or proliferation of cells is not however restricted or limited to the coronary arteries. It can also occur post operatively causing restenosis in for example peripheral vascular systems.
A number of proposals have been made in the prior art to prevent restenosis.
U.S. Pat. No. 5,087,244 (Wolinsky et al.) purports to teach the use of a catheter having an inelastic balloon at one end thereof, where the balloon has minute perforations and contains a concentrated heparin solution which will be released through the perforations contacting an area of the artery after angioplasty to prevent restenosis.
U.S. Pat. No. 5,116,864 (Hathaway et al.) purports to teach the prevention of restenosis in peripheral or cardiac vascular systems after vascular recanalisation by systemic administration of photo activatable psoralen to give serum psoralen levels which inhibit smooth muscle cell growth.
U.S. Pat. No. 5,092,841 (Spears, J. R.) purports to teach the treatment of an arterial wall injured during angioplasty by delivering bio-protective material between the wall and the angioplasty catheter so that the bio-protective material is entrapped and permeates into the tissues and vessels of the arterial wall during opposition of the angioplasty catheter.
EP 356275-A (Petitou et al.) purports to teach the use of new o-acylated glycosamino-glycan derivatives in the inhibition of post-operative restenosis.
Berk., B. C. et al in the J. Am. Coll. Cardiol. dated 1991 Vol. 17 #6 Supplement B, pp 111B-117B purports to discuss the pharmacologic roles of heparin and glucocorticoids to prevent restenosis after coronary angioplasty.
WO 9209561 (Itoh et al.) purports to teach the use of new ACAT inhibiting amide derivatives in treatment of restenosis after percutaneous transluminal coronary angioplasty.
WO 9208472 (Scarborough et al.) purports to teach the use of platelet antiadhesive peptide(s) obtained from snake venom for the prevention of restenosis following angioplasty.
WO 9207852 (Bovy et al.) purports to teach the use of certain biphenylalkyl xanthine derivatives to prevent post-angioplasty restenosis.
WO 9205782 (Pill, J.) purports to teach the use of thromboxane-A2-receptor antagonists (I) in the preparation of medicaments for inhibition of proliferative developments in obstructive vascular disorders ie. arterial restenosis.
WO 9118639 (GAj et al.) purports to teach the inhibition of stenosis after balloon angioplasty, by the administration of fibronectin by continuous or bolus infusion, or by direct infusion into the stenotic region via the angioplasty catheter.
CA 2,042,159 laid open application (Ondetti, et al.) purports to teach the use of ACE inhibitor (via the oral or parenteral route) for preventing or reducing the risk of restenosis following angioplasty.
U.S. Pat. No. 4,929,602 (Harker, et al.) purports to teach a method of inhibiting arterial restenosis by administration of D-phenyl alanyl-prolyl-arginyl-balomethyl ketone peptide derivative or a hydrolalin acid addition thereof.
U.S. Pat. No. 4,820,732 (Shell, et al.) purports to teach a composition containing a prostaglandin compound for the reduction of restenosis and abrupt-stenosis.
Applicant is also aware of a company Glycomed developing a fragment of Heparin that prevents arterial restenosis after balloon angioplasty.
In the basic research efforts in the latter '70s and the early 80's, there existed considerable confusion as to what role immunotherapy should take in cancer. Activation or “hyping” of macrophages was thought to be important. However, in an examination by Romans and Falk of peritoneal macrophages obtained from patients with neoplastic disease, there was definite evidence that these macrophages were already activated yet were co-existing with cancer cells and not causing their destruction.
It has been shown by several independent investigators that the malfunction of macrophages or the putitive block is due to excessive prostaglandin and that this can be altered in tissue culture by corticosteroids, ASA, and the non-steroidal anti-inflammatory drugs, i.e. indomethacin, and naproxen (Naprosyn™). Again, in animal tumors it was repeatedly demonstrated that these substances could alter the response to neoplastic cells and that various combinations of these substances employed with immune enhancing agents could produce very credible success in eliminating experimental tumors. Lala and co-workers combined Indomethacin therapy with Interleukin 2 and showed that this could effect a cure with experiment neoplasm.
There were continued problems with the use of any of these agents in the actual human in vivo experience. All of the non-steroidal anti-inflammatory agents (NSAID) produced major toxicity in terms of gastro-intestinal, neurological, and other areas. Thus, the basis of the present approach is that under general circumstances the use of these agents in human disease, in sufficient amounts, the drug will penetrate to any pathological tissue to alter therapeutically local prostaglandin production. While intravenous preparations exist of Indomethacin and now of other agents, the data is overwhelming, that using these drugs alone produces prohibitive side effects in human subjects. Therefore only insufficient amounts can be brought into the body to effect more than occasional responses in neoplasm.
However the majority of the evidence is present to indicate and therefore it can be postulated that the basis for neoplastic development and how the initial cell “sneaks by” the immune surveillance mechanism relates to its production of prostaglandin. One need postulate only one mutation to alter the amount of prostaglandin synthesis produced by cells when they become “malignant” to establish a mechanism of blocking out the initial cell in any immune reaction, i.e. the macrophage. It therefore became essential to develop a combination of NSAIDS for clinical use to produce a major improvement in response in neoplastic disease and other conditions where excessive prostaglandin synthesis represents the basis of the pathogenesis of this disease state, i.e. arthritis, and various others of the so-called connective tissue inflammatory disorders and/or auto-aggressive diseases.
See also:                1. Modulation of Immunity in Cancer Patients by Prostaglandin Antagonists, Immunity to Cancer II, Alan R. Liss, Inc.; and        2. Goodwin, J. S. (1981) Prostaglandin E and Cancer Growth Potential for Immunotherapy with Prostaglandin Synthesis Inhibitors, Augmentive Agents in Cancer Therapy, Raven Press, New York.        
It is therefore an object of this invention to provide a method of treatment and formulations and pharmaceutical compositions for preventing arterial restenosis after for example balloon angioplasty when endothelial cell proliferation occurs on the inner arterial wall caused by irritation to the cells by balloon angioplasty.
It is a further object of the invention to provide such treatment using hyaluronic acid which is safe and essentially non-toxic.
It is a further object of the invention to provide methods of treatment and formulations and pharmaceutical compositions generally for preventing restenosis and inhibiting restenosis for example post operatively in peripheral vascular systems.
Further and other objects of the invention will be realized by persons skilled in the art from the following summary of the invention and discussion with respect thereto.